Score a victory for Microsoft, which was apparently able to ink a deal with Amazon to make Bing the default search engine on the e-tailer's new batch of Kindle Fire devices. If you're not down with Bing, don't worry, Amazon is giving users the option of switching their default search provider to other services, like Google (hooray!) or Yahoo (as if!).

One thing to keep in mind if you pick up a Kindle Fire is that, in theory, Amazon could change your default search provider at any time, or at least that's how it's worded in Amazon's terms and conditions.

"All text you enter in Amazon Silks address bar is sent to a default search engine. The initial default search engine is selected by Amazon Silk, and we may change the default search engine in the future without notice to you," Amazon states. "If you would like, you may choose to use a different search provider s your default search engine."

In other words, even if you change your default search provider, don't be surprised if it switches back to Bing at some point, particularly after a software update.

So, why is this a big deal for Microsoft? The thing to keep in mind with browsers is that even though they're free to use, they generate copious amounts of cash in ad revenue, which is the reason browser makers are constantly jockeying for position on new devices. Details of Microsoft's deal with Amazon haven't been disclosed, but you can bet Microsoft forked over a big chunk of cash to make this happen. To put this into perspective, in 2010 Google paid Mozilla $103 million to be featured as the default search engine in Firefox, which represented 84 percent of Mozilla's total revenue for that year. Google and Mozilla struck a new deal in 2011 that was reportedly worth nearly $300 million annually, or just under $1 billion for the life of the contract.

Regardless of the money involved, are users better off using Bing or is Google the better search engine? To help you answer that question, try out Microsoft's new "Bing It On" challenge and see which one works better for you.